/*
* $Id: MD5Sum.cpp 4483 2008-01-02 09:19:06Z soarchin $
* 
* this file is part of easyMule
* Copyright (C)2002-2008 VeryCD Dev Team ( strEmail.Format("%s@%s", "emuledev", "verycd.com") / http:* www.easymule.org )
* 
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
* 
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
* 
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "stdafx.h"
#include "MD5Sum.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif



MD5Sum::MD5Sum()
{
}

MD5Sum::MD5Sum(const CString& sSource)
{
	Calculate(sSource);
}

MD5Sum::MD5Sum(const unsigned char* pachSource, UINT nLen)
{
	Calculate(pachSource, nLen);
}

CString MD5Sum::Calculate(const CString& sSource)
{
	return Calculate((const unsigned char*)(LPCTSTR)sSource, sSource.GetLength()*sizeof(TCHAR));
}

CString MD5Sum::Calculate(const unsigned char* pachSource, UINT nLen)
{
	MD5_CTX context;

	MD5Init(&context);
	MD5Update(&context, pachSource, nLen);
	MD5Final(m_rawHash, &context);

	m_sHash.Empty();
	for (int i = 0; i < 16; i++)
	{
		CString sT;
		sT.Format(_T("%02x"), m_rawHash[i]);
		m_sHash += sT;
	}

	return m_sHash;
}

CString MD5Sum::GetHash() const
{
	return m_sHash;
}

#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21

static void MD5Transform (UINT4 [4], const unsigned char [64]);
static void Encode (unsigned char*, const UINT4*, unsigned int);
static void Decode (UINT4*, const unsigned char*, unsigned int);
static void MD5_memcpy (POINTER, POINTER, unsigned int);
static void MD5_memset (POINTER, int, unsigned int);

static unsigned char PADDING[64] = {
  0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

/* F, G, H and I are basic MD5 functions.
*/
#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))

/* ROTATE_LEFT rotates x left n bits.
	15-April-2003 Sony: use MSVC intrinsic to save some cycles
*/
#ifdef _MSC_VER
#pragma intrinsic(_rotl)
#define ROTATE_LEFT(x, n) _rotl((x), (n))
#else
#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
#endif

/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
Rotation is separate from addition to prevent recomputation.
*/
#define FF(a, b, c, d, x, s, ac) { \
 (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define GG(a, b, c, d, x, s, ac) { \
 (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define HH(a, b, c, d, x, s, ac) { \
 (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }
#define II(a, b, c, d, x, s, ac) { \
 (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
 (a) = ROTATE_LEFT ((a), (s)); \
 (a) += (b); \
  }

/* MD5 initialization. Begins an MD5 operation, writing a new context.
*/
void MD5Init (MD5_CTX*context)
{
  context->count[0] = context->count[1] = 0;
  /* Load magic initialization constants.
*/
  context->state[0] = 0x67452301;
  context->state[1] = 0xefcdab89;
  context->state[2] = 0x98badcfe;
  context->state[3] = 0x10325476;
}

/* MD5 block update operation. Continues an MD5 message-digest
  operation, processing another message block, and updating the
  context.
*/
void MD5Update (MD5_CTX*context, const unsigned char*input, unsigned int inputLen)
{
  unsigned int i, index, partLen;

  /* Compute number of bytes mod 64*/
  index = (unsigned int)((context->count[0] >> 3) & 0x3F);

  /* Update number of bits*/
  if ((context->count[0] += ((UINT4)inputLen << 3))
   < ((UINT4)inputLen << 3))
 context->count[1]++;
  context->count[1] += ((UINT4)inputLen >> 29);

  partLen = 64 - index;

  /* Transform as many times as possible.
*/
  if (inputLen >= partLen) {
 MD5_memcpy
   ((POINTER)&context->buffer[index], (POINTER)input, partLen);
 MD5Transform (context->state, context->buffer);

 for (i = partLen; i + 63 < inputLen; i += 64)
   MD5Transform (context->state, &input[i]);

 index = 0;
  }
  else
 i = 0;

  /* Buffer remaining input*/
  MD5_memcpy
 ((POINTER)&context->buffer[index], (POINTER)&input[i],
  inputLen-i);
}

/* MD5 finalization. Ends an MD5 message-digest operation, writing the
  the message digest and zeroizing the context.
*/
void MD5Final (unsigned char digest[16], MD5_CTX*context)
{
  unsigned char bits[8];
  unsigned int index, padLen;

  /* Save number of bits*/
  Encode (bits, context->count, 8);

  /* Pad out to 56 mod 64.
*/
  index = (unsigned int)((context->count[0] >> 3) & 0x3f);
  padLen = (index < 56) ? (56 - index) : (120 - index);
  MD5Update (context, PADDING, padLen);

  /* Append length (before padding)*/
  MD5Update (context, bits, 8);
  /* Store state in digest*/
  Encode (digest, context->state, 16);

  /* Zeroize sensitive information.
*/
  MD5_memset ((POINTER)context, 0, sizeof (*context));
}

/* MD5 basic transformation. Transforms state based on block.
*/
static void MD5Transform (UINT4 state[4], const unsigned char block[64])
{
  UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];

  Decode (x, block, 64);

  /* Round 1*/
  FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1*/
  FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2*/
  FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3*/
  FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4*/
  FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5*/
  FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6*/
  FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7*/
  FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8*/
  FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9*/
  FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10*/
  FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11*/
  FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12*/
  FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13*/
  FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14*/
  FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15*/
  FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16*/

 /* Round 2*/
  GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17*/
  GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18*/
  GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19*/
  GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20*/
  GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21*/
  GG (d, a, b, c, x[10], S22,  0x2441453); /* 22*/
  GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23*/
  GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24*/
  GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25*/
  GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26*/
  GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27*/
  GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28*/
  GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29*/
  GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30*/
  GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31*/
  GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32*/

  /* Round 3*/
  HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33*/
  HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34*/
  HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35*/
  HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36*/
  HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37*/
  HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38*/
  HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39*/
  HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40*/
  HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41*/
  HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42*/
  HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43*/
  HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44*/
  HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45*/
  HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46*/
  HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47*/
  HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48*/

  /* Round 4*/
  II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49*/
  II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50*/
  II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51*/
  II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52*/
  II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53*/
  II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54*/
  II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55*/
  II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56*/
  II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57*/
  II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58*/
  II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59*/
  II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60*/
  II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61*/
  II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62*/
  II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63*/
  II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64*/

  state[0] += a;
  state[1] += b;
  state[2] += c;
  state[3] += d;

  /* Zeroize sensitive information.
*/
  MD5_memset ((POINTER)x, 0, sizeof (x));
}

/* Encodes input (UINT4) into output (unsigned char). Assumes len is
  a multiple of 4.
*/
static void Encode (unsigned char*output, const UINT4*input, unsigned int len)
{
  unsigned int i, j;

  for (i = 0, j = 0; j < len; i++, j += 4) {
 output[j] = (unsigned char)(input[i] & 0xff);
 output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
 output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
 output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
  }
}

/* Decodes input (unsigned char) into output (UINT4). Assumes len is
  a multiple of 4.
*/
static void Decode (UINT4*output, const unsigned char*input, unsigned int len)
{
  unsigned int i, j;

  for (i = 0, j = 0; j < len; i++, j += 4)
 output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
   (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
}

/* Note: Replace "for loop" with standard memcpy if possible.
*/

static void MD5_memcpy (POINTER output, POINTER input, unsigned int len)
{
  unsigned int i;

  for (i = 0; i < len; i++)
 output[i] = input[i];
}

/* Note: Replace "for loop" with standard memset if possible.
*/
static void MD5_memset (POINTER output, int value, unsigned int len)
{
  unsigned int i;

  for (i = 0; i < len; i++)
 ((char*)output)[i] = (char)value;
}
